Solar Wind - Micro Power Generation » Definitions http://www.micro-generator.com Blogging about wind and solar power at home Wed, 23 Sep 2009 18:01:21 +0000 http://wordpress.org/?v=2.7.1 en hourly 1 Micro-Generation of Wind Power - Some Definitions http://www.micro-generator.com/2006/05/11/micro-generation-of-wind-power-some-definitions/ http://www.micro-generator.com/2006/05/11/micro-generation-of-wind-power-some-definitions/#comments Thu, 11 May 2006 20:12:19 +0000 ashleys http://www.micro-generator.com/2006/05/11/micro-generation-of-wind-power-some-definitions/ In this section I would like to focus on the some relevant definitions with respect to the micro-generation of wind power. First a set of more general definitions followed by definitions more specifically relevant to wind power. A lot of these definitions are also available on the great online resource wikipedia, and where relevant I have included a link.

General

Ampere-hour (Ah): Quantity of electricity or measure of charge. (1 Ah = 3600 C [Coulomb])

Electrical grid: An integrated system of electricity distribution, usually covering a large area.

Kilowatt (kW): 1000 watts.

Kilowatt-hour (kWh): One thousand watts acting over a period of 1 hour. The kWh is a unit of energy.

Micro-generation: Defined as generation of a capacity of less than 50 kW. Although there has been some discussion about this.

ROC: Renewable Obligtion Certificate - A certificate that is issued to accrediated generators for each MWh of electricity that is produced from renewable sources. ROC’s can be traded and have a value of approximately £46/MWh, though the value will obviously vary due to market conditions

Wind Power

Constant-speed wind turbines: Turbines that operate at a constant rotor revolutions per minute (RPM) and are optimized for energy capture at a given rotor diameter at a particular speed in the wind power curve.

HAWT: Horizontal Axis Wind Turbine - The most common form of wind turbine in which, as the name suggests, the blades rotate around the horizontal. This is of course the form that most people will be familiar with.

VAWT: Vertical Axis Wind Turbine - In this case the turbine blades rotate about the vertical axis. This design is less common although a number are now being developed for the micro-generation market.

Wind turbines can be classified depending on the blade diameter:

Micro: Less than 1.25 metres

Small: Between 1.25 and 2 metres

Large: Greater than 2 metres

]]> http://www.micro-generator.com/2006/05/11/micro-generation-of-wind-power-some-definitions/feed/ Micro-Generation Definition debated in UK Parliment http://www.micro-generator.com/2006/04/28/micro-generation-definition-debated-in-uk-parliment/ http://www.micro-generator.com/2006/04/28/micro-generation-definition-debated-in-uk-parliment/#comments Fri, 28 Apr 2006 09:47:12 +0000 ashleys http://www.micro-generator.com/?p=6 It seems that not everyone agrees with the official UK definition of micro-generation as generation of a capacity of less than 50 kW. As we pointed out the yesterday the peak demand for a house in the winter would be around 20kW. So at least from a residential point of view 50 kW seems plenty.

In discussion in the UK Parliment for the “Climate Change and Sustainable Energy Bill” there was a fairly intense discussion (osl) about using 50kW as the the threshold in the definition of micro-generation. After reading the debate it seems to me that nobody had definitive information on what the average demand for an average house would be. Also it wasn’t the clear what the objection was to the threshold was. It was either:
  • (a) The danger that people would suddenly start creating wind farms in the gardens to ensure that used all the generation capacity available to them under the definition of micro-generation, or
  • (b) The fact that people would want to sell their excess capacity back to the grid.
Perhaps both! I am fairly sure that market forces would tend to ensure that (a) wouldn’t happen, and as far as I am concerned (b) is exactly want we want!
]]> http://www.micro-generator.com/2006/04/28/micro-generation-definition-debated-in-uk-parliment/feed/ Micro-Generation a Definition http://www.micro-generator.com/2006/04/27/micro-generation-a-definition/ http://www.micro-generator.com/2006/04/27/micro-generation-a-definition/#comments Thu, 27 Apr 2006 16:38:32 +0000 ashleys http://www.micro-generator.com/?p=5 You would think it would be easy to define something like micro-generation. Well perhaps you wouldn’t, but I certainly did. But as with a lot of things, it means different things to different people. The UK Goverment through the means of the Energy Act 2004 (osl) defines micro-generation as generation of a capacity of less than 50 kW.

Which as James Keirstead points out (osl) is more than enough for most households, whose winter peak demand is usually about 20kW. Actually James on his blog Small is beautiful (osl) has done a nice job on a more complete definition and I recommend you check it out.

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